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The SAFE (Surgery, Antibiotics, Facial cleanliness, Environmental improvement) strategy is the WHO's endorsed approach for eliminating trachoma as a public health problem; however, not all components have been treated equally. Historically, the F and E components have not been prioritized owing to their perceived complexity. With school enrollment increasing in Ethiopia, development of a national school health program that is focused on the F and E components represents an opportunity to strengthen the SAFE strategy in the country. In 2016, the Trachoma Control Program in Amhara, Ethiopia, along with its partners, developed a School Trachoma Program (STP) that offers grade-specific lessons to improve sanitation and hygiene knowledge and practices among primary school-aged children. To assess its impact, schools were sampled before implementation and then up to 1 year after STP rollout. The aim of this report is to detail STP outcomes and the associations between outcomes and school-level variables. By 2018, adoption of an STP was strong within Amhara, with 85% of the 137 surveyed schools completing their quarterly reports and nearly 80% having at least one teacher trained in the STP. By the end of the third quarter, nearly all schools (86%) had access to a latrine, and 89% of students had a clean face. A schoolwide orientation was associated with increased STP lessons and activities (P = 0.01). Development of an STP, with buy-in from principals and teachers, represents a promising approach for the adoption of a new F- and E-specific curriculum and may help advance efforts to eliminate trachoma.

Purpose: To evaluate how changes in visual acuity are associated with changes in quality of life (QoL) among patients with non-infectious uveitis taking antimetabolites., Methods: This secondary analysis of the multicenter First-line Antimetabolites as Steroid-sparing Treatment (FAST) Uveitis Trial involves 216 participants randomized to methotrexate or mycophenolate mofetil. Vision-related (NEI-VFQ and IND-VFQ) and health-related (PCS and MCS SF-36v2) QoL and visual acuity were measured at baseline and 6-month primary endpoint., Results: Visual acuity was significantly associated and correlated with all QoL measures (Spearman correlation coefficients = 0.5, 0.5, 0.3, and 0.4 for NEI-VFQ, IND-VFQ, SF-36v2 MCS and PCS, respectively). All observed changes in QoL met or exceeded the minimal clinically important difference definition on each scale. Treatment group was not significantly associated with any QoL measure., Conclusion: By adding insight beyond visual acuity, QoL provides a more comprehensive picture of the patient experience during uveitis treatment. Abbreviations and Acronyms: QoL = quality of life; VR-QoL = vision-related quality of life; HR-QoL = health-related quality of life; FAST = First-line Antimetabolites as Corticosteroid Sparing Treatment; NEI-VFQ = National Eye Institute Visual Functioning Questionnaire; IND-VFQ = Indian Visual Functioning Questionnaire; SF-36v2 = Medical Outcomes Study 36-Item Short Form Survey; PCS = physical component score; MCS = mental component score; 95% CI = 95% confidence interval; MCID = minimal clinically important difference.

Purpose: To evaluate the outcomes of uveitic macular edema at 6 and 12 months in patients treated with methotrexate or mycophenolate mofetil., Design: Subanalysis of a block-randomized, observer-masked, multicenter clinical trial., Participants: Patients were enrolled in the First-line Antimetabolites as Steroid-sparing Treatment (FAST) Uveitis Trial between August 2013 and August 2017., Methods: Patients were randomized to oral methotrexate 25 mg weekly or mycophenolate mofetil 1.5 g twice daily for 12 months, along with a corticosteroid taper. In addition to standardized clinical examination, all patients underwent spectral-domain OCT imaging at each visit. At the 6-month primary end point, patients who achieved treatment success continued the same treatment for a subsequent 6 months, and treatment failures switched to the other treatment group., Main Outcome Measures: Prespecified 6-month primary outcome and 12-month outcomes of central subfield thickness and visual acuity., Results: Of 216 patients in the FAST Trial, 42 eyes (30 patients) in the methotrexate group and 55 eyes (41 patients) in the mycophenolate group had uveitic macular edema. Baseline median central subfield thickness was 359 μm and 342 μm in the methotrexate and mycophenolate groups, respectively. At 12 months, for those who stayed on the same treatment, macular thickness decreased from baseline by 30.5 μm (interquartile range [IQR], -132.3 to 4.0) and 54 μm (IQR, -95.5 to -4.5) in the methotrexate and mycophenolate groups, respectively (P = 0.73). In patients who switched treatment at 6 months, macular thickness decreased from baseline by 12.5 μm (IQR, -32.3 to -0.5) and 50 μm (IQR, -181.0 to -10.0) in the methotrexate and mycophenolate groups, respectively (P = 0.34). At 12 months, 7 of 19 eyes (37%) on methotrexate had resolution of macular edema compared with 15 of 25 eyes (60%) on mycophenolate (P = 0.10). For those who switched treatments, 8 of 17 eyes (47%) on methotrexate and 6 of 11 eyes (55%) on mycophenolate had resolution of macular edema (P = 0.92)., Conclusions: Treatment with methotrexate or mycophenolate mofetil for uveitic macular edema results in similar improvements in macular thickness at 6 and 12 months. At 12 months, approximately half of eyes in each antimetabolite group still had persistent macular edema., (Copyright © 2022 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Background: The incidence of herpes zoster (HZ) has been increasing in recent decades. Although 2 vaccines for HZ are available, there have been few studies on the incidence rates of HZ and postherpetic neuralgia (PHN) since their introduction. This study examined the incidence rates of HZ and PHN from 1994 to 2018 in the United States to determine if they have continued to increase since introduction of the HZ vaccines., Methods: A de-identified longitudinal administrative claims database, the OptumLabs Data Warehouse, was used to assess incidence rates among individuals continuously enrolled in the database for ≥365 days with no prior history of HZ or PHN. Unstandardized and standardized incidence rates were calculated by year, 10-year age groups, sex, and race/ethnicity., Results: There were 610 766 individuals with HZ (median age, 56.3; interquartile range, 43.0-68.7 years; 59.8% women; 70.6% white). From 1994 to 2018, the incidence of HZ increased from 286.0 (95% confidence interval [CI], 259.1-312.8) to 579.6 (95% CI, 554.2-605.0) cases per 100 000 person-years, an annual increase of 3.1% (95% CI, 2.5-3.6%). Since 2007, annual HZ incidence rates have decreased in individuals ≤20 and >60 years old. The overall incidence rate of PHN was 57.5 (95% CI, 56.0-59.0) cases per 100 000 person-years. The proportion of individuals with HZ who developed PHN was higher from 2007 to 2018 than from 1994 to 2006., Conclusions: HZ incidence rates have continued to increase in age groups for which HZ vaccines are not currently recommended, warranting a review of current vaccine recommendations., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Purpose: To evaluate changes in health-related and vision-related quality of life (VRQoL) among patients with noninfectious uveitis who were treated with antimetabolites., Design: Secondary analysis of a randomized controlled trial., Participants: Patients with noninfectious uveitis from India, the United States, Australia, Saudi Arabia, and Mexico., Methods: From 2013 through 2017, 216 participants were randomized to receive 25 mg weekly oral methotrexate or 1.5 g twice daily oral mycophenolate mofetil. Median changes in quality of life (QoL) were measured using Wilcoxon signed-rank tests, and differences between treatment groups were measured using linear mixed models, adjusting for baseline QoL score, age, gender, and site. Among Indian patients, VRQoL scores from a general scale (the National Eye Institute Visual Function Questionnaire [NEI-VFQ]) and a culturally specific scale (the Indian Visual Function Questionnaire [IND-VFQ]) were compared using Pearson correlation tests., Main Outcome Measures: Vision-related QoL (NEI-VFQ and IND-VFQ) and health-related QoL (HRQoL; physical component score [PCS] and mental component score [MCS] of the Medical Outcomes Study 36-Item Short Form Survey [SF-36v2]) were measured at baseline, the primary end point (6 months or treatment failure before 6 months), and the secondary end point (12 months or treatment failure between 6 and 12 months)., Results: Among 193 participants who reached the primary end point, VRQoL increased from baseline by a median of 12.0 points (interquartile range [IQR], 1.0-26.1, NEI-VFQ scale), physical HRQoL increased by a median of 3.6 points (IQR, -1.4 to 14.9, PCS SF-36v2), and mental HRQoL increased by a median of 3.0 points (IQR, -3.7 to 11.9, MCS SF-36v2). These improvements in NEI-VFQ, SF-36v2 PCS, and SF-36v2 MCS scores all were significant (P < 0.01). The linear mixed models showed that QoL did not differ between treatment groups for each QoL assessment (NEI-VFQ, IND-VFQ, PCS SF-36v2, and MCS SF-36v2; P > 0.05 for all). The NEI-VFQ and IND-VFQ scores for Indian participants were correlated highly at baseline and the primary and secondary end points (correlation coefficients, 0.87, 0.80, and 0.90, respectively)., Conclusions: Among patients treated with methotrexate or mycophenolate mofetil for uveitis, VRQoL and HRQoL improved significantly over the course of 1 year and did not differ by treatment allocation. These findings suggest that antimetabolites could improve overall patient well-being and daily functioning., (Copyright © 2021 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Background: Trachomatous scarring (TS) results from repeated infection with the bacterium Chlamydia trachomatis. Pronounced scarring is an underlying cause of trachomatous trichiasis (TT) that can lead to blindness. Since the condition is irreversible, TS in adults has been considered a marker of past exposure to trachoma infection. The aim of this report was to estimate the population-based prevalence of TS within Amhara, Ethiopia, a region with a historically high burden of trachoma., Methods: District-level multi-stage cluster surveys were conducted in all districts between 2010 and 2015 to monitor the impact of approximately 5 years of trachoma interventions. Approximately 40 households were sampled per cluster and all participants ages ≥ 1 year were graded for the 5 World Health Organization simplified signs. Before each survey round, trachoma graders participated in a 7-day training and reliability exam that included cases of TS. TS prevalence estimates were weighted to account for sampling design and adjusted for age and sex using post-stratification weighting., Results: Across the 152 districts in Amhara, 208,510 individuals ages 1 year and older were examined for the signs of trachoma. Region-wide, the prevalence of TS was 8.2 %, (95 % Confidence Interval [CI]: 7.7-8.6 %), and the prevalence among individuals ages 15 years and older (n = 110,137) was 12.6 % (95 % CI: 12.0-13.3 %). District-level TS prevalence among individuals ages 15 years and older ranged from 0.9 to 36.9 % and was moderately correlated with district prevalence of TT (r = 0.31; P < 0.001). The prevalence of TS increased with age, reaching 22.4 % among those ages 56 to 60 years and 24.2 % among those ages 61 to 65 years. Among children ages 1 to 15 years TS prevalence was 2.2 % (95 % CI: 1.8-2.8 %), increased with age (P < 0.001), and 5 % of individuals with TS also had trachomatous inflammation-intense (TI)., Conclusions: These results suggest that Amhara has had a long history of trachoma exposure and that a large population remains at risk for developing TT. It is promising, however, that children, many born after interventions began, have low levels of TS compared to other known trachoma-hyperendemic areas.

Background: Juvenile idiopathic arthritis (JIA)-associated uveitis is a chronic paediatric ocular inflammatory condition that can result in visual impairment. Adalimumab, a tumour necrosis factor (TNF)-alpha inhibitor, effectively controls joint and eye inflammation; however, its long-term use may increase the risk of adverse health outcomes and place an undue financial burden on the patient and healthcare system given its high cost. There is great interest for patients to stop adalimumab following remission due to these reasons but there is a lack of information on the ability to maintain control after discontinuing adalimumab., Methods: The Adalimumab in Juvenile Idiopathic Arthritis-associated Uveitis Trial (ADJUST) is a multicentred, international trial that will randomise 118 participants aged 2 years and older with controlled JIA-associated uveitis to either continue adalimumab or discontinue adalimumab and receive a placebo. The trial will compare the time to uveitis recurrence between the two groups over 12 months. All participants will receive the standard weight-based dose of adalimumab or placebo: 20 mg biweekly (if < 30 kg) or 40 mg biweekly (if ≥ 30 kg)., Discussion: This is the first randomised controlled trial to assess the efficacy of discontinuing adalimumab after demonstrating control of JIA-associated uveitis for at least 12 months. The results of ADJUST will provide information on clinical outcomes to guide clinicians in their decision-making regarding discontinuation of adalimumab., Trial Registration: ClinicalTrials.gov NCT03816397. Registered on 25 January 2019. EudraCT 2019-000412-29. Registered on 17 January 2019.

Importance: Methotrexate and mycophenolate mofetil are commonly used immunomodulatory therapies for achieving corticosteroid-sparing control of noninfectious uveitis, but there is uncertainty about which drug is more effective., Objective: To compare the effect of methotrexate and mycophenolate for achieving corticosteroid-sparing control of noninfectious intermediate uveitis, posterior uveitis, and panuveitis., Design, Setting, and Participants: The First-line Antimetabolites as Steroid-sparing Treatment (FAST) uveitis trial screened 265 adults with noninfectious uveitis requiring corticosteroid-sparing immunosuppressive therapy from 9 referral eye centers in India, the United States, Australia, Saudi Arabia, and Mexico between August 22, 2013, and August 16, 2017. Follow-up ended on August 20, 2018., Interventions: Patients were randomized to receive oral methotrexate, 25 mg weekly (n = 107), or oral mycophenolate mofetil, 3 g daily (n = 109)., Main Outcomes and Measures: The primary outcome was treatment success at 6 months, which was defined as having control of inflammation in both eyes, no more than 7.5 mg prednisone daily and less than or equal to 2 drops of prednisolone acetate 1%, and no treatment failure due to safety or intolerability. Patients underwent follow-up to 12 months while receiving the same treatment or switched to the other antimetabolite, depending on their 6-month outcome., Results: Among 216 patients who were randomized (median age, 38 years; 135 (62.5%) women), 194 (89.8%) completed follow-up through 6 months. Treatment success occurred in 64 (66.7%) patients in the methotrexate group vs 56 (57.1%) in the mycophenolate group (difference, 9.5% [95% CI, -5.3% to 21.8%]; odds ratio [OR], 1.50 [95% CI, 0.81 to 2.81]; P = .20). Among patients with posterior uveitis or panuveitis, treatment success was achieved in 58 (74.4%) in the methotrexate group vs 42 (55.3%) in the mycophenolate group (difference, 19.1% [95% CI, 3.6% to 30.6%]; OR, 2.35 [95% CI, 1.16 to 4.90]; P = .02); whereas among patients with intermediate uveitis treatment success occurred in 6 (33.3%) in the methotrexate group vs 14 (63.6%) in the mycophenolate group (difference, -30.3% [95% CI, -51.6% to 1.1%]; OR, 0.29 [95% CI, 0.08 to 1.05]; P = .07; P for interaction = .004). Elevated liver enzymes were the most common nonserious laboratory adverse event, occurring in 14 patients (13.0%) in the methotrexate group and 8 patients (7.4%) in the mycophenolate group., Conclusions and Relevance: Among adults with noninfectious uveitis, the use of mycophenolate mofetil compared with methotrexate as first-line corticosteroid-sparing treatment did not result in superior control of inflammation. Further research is needed to determine if either drug is more effective based on the anatomical subtype of uveitis., Trial Registration: ClinicalTrials.gov Identifier: NCT01829295.

Objectives: Mass drug administration (MDA) with azithromycin is a core component of the WHO-recommended strategy to eliminate trachoma as a public health problem, but low participation rates in MDA campaigns may undermine the effectiveness of this intervention. We explored factors associated with individual MDA participation at the individual, head of household and household levels in Amhara, Ethiopia., Methods: We conducted four district-level, multilevel cluster random coverage surveys to collect data on self-reported MDA participation and predictors. Random-effects logistic regression modelling was used to identify correlates of MDA participation while adjusting for nesting of individuals at the household and village level., Results: The district-level self-reported participation in the trachoma MDA ranged from 78.5% to 86.9%. Excellent and fair health status (Odds ratio [OR] = 5.77; 95% Confidence interval [CI]: 3.04, 10.95; OR = 7.08; 95% CI: 3.47, 14.46), advanced knowledge of the MDA campaign (OR = 2.93; 95% CI: 2.04, 4.21) and knowledge of trachoma (OR = 1.60; 95% CI: 1.17, 2.19) were all positively associated with MDA participation. When excluding heads of household from the model, correlates retained similar positive associations to participation, in addition to the head of household participation (OR = 3.34; 95% CI: 2.46, 4.54)., Conclusions: To increase the impact of MDA campaigns, MDA mobilisation strategies-including comprehensive trachoma and azithromycin messaging and MDA campaign awareness-should target heads of household, those in poorer health and older age groups., (© 2019 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.)

Purpose: The EDPGFFNVE nonapeptide (NP) was recognized as the CD21 (CR2) binding epitope of the Epstein-Barr virus (EBV) gp350/ 220 envelope glycoprotein which mediates the virus attachment to human B lymphocytes (Nemerow et al., Cell 56:369-377, 1989). Here we evaluated the targeting potential of a synthetic receptor binding epitope (NP) covalently attached to a water-soluble polymeric drug carrier. In particular, the biorecognition of N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-NP conjugates by B- and T-cells and the cytotoxicity of HPMA copolymer-NP-adriamycin (ADR) conjugates toward B-cells, T-cells, and peripheral blood lymphocytes (PBL) were evaluated., Methods: HPMA copolymer-NP and optionally ADR conjugates varying in the NP density and mode of NP attachment were incubated with Raji B-cells (human Burkitt's lymphoma), CCRF-CEM T-cells (acute human lymphoblastic leukemia), and CCRF-HSB-2 T-cells (human lymphoblastic leukemia). The kinetics of binding was studied, the Langmuir adsorption isotherms analyzed, binding constants calculated, and IC50 doses determined., Results: Flow cytometry studies revealed that binding was homogeneous to both cell types. The apparent binding constants to T-cells were about two times higher when compared to B-cells. The binding and cytotoxicity increased with increased amount of epitopes per polymer chain. Attachment of the NP via a GFLG spacer resulted in increased biorecognition when compared with conjugates containing NP bound via a GG spacer. HPMA copolymer-NP-ADR conjugates possessed specific cytotoxicity to T- and B-malignant cells. Concentrations, which were lethal to the latter, were not toxic for PBL., Conclusions: The data obtained seem to indicate the potential of the HPMA copolymer-NP conjugates as polymer anticancer drug carriers targetable to immunocompetent cells.

The solution properties of aqueous ethanol donor solutions were characterized for the particular case of an increased flux nitroglycerin transdermal system. Permeation through porous and nonporous polymer membranes was investigated and modelled. While the permeation of ethanol through the porous membranes is adequately described by theory, clogging of pores occurs in the presence of lactose. Permeation through ethylene vinyl acetate membranes reflects interactions of the solute and solvent with the polymer.

The self-association of insulin monomers into oligomers and macromolecular aggregates leads to complications in the administration of insulin, both in conventional administration and in the development of long-term insulin delivery systems. These problems are aggravated by the tendency of insulin to adsorb onto the surface of solution containers and infusion devices. Furthermore, with insulin infusion devices, shear rates can be generated which can accelerate the self-association and surface adsorption processes. The effects of urea on shear-induced insulin self-association and surface adsorption were investigated. It was found that the addition of a certain concentration range of urea to insulin solutions greatly reduces both insulin self-association and surface adsorption. Circular dichroic studies established that these concentrations of urea also preserve insulin conformation under high shear rates, where conformations are altered without urea. Higher urea concentrations lead to insulin denaturation and accelerated self-association.

An optimal concentration range of aqueous ethanol produces 5-10-fold increases in nitroglycerin flux across skin and ethanol skin permeation that are far greater than reported previously. For aqueous ethanol solutions saturated with nitroglycerin with an ethanol volume fraction less than or equal to 0.7, the flux of nitroglycerin across skin is linear with the ethanol flux and is traced to a linear solubility relationship and a constant diffusion coefficient.

In summary, PGI2 is approximately 3 orders of magnitude more potent than PGE1 in the prevention of platelet aggregation. Similarly PGE1 is an order of magnitude more potent than PGD2 (ID50's = 5.3 x 10(-10) M, 1.3 x 10(-7) M and 1.4 x 10(-6) M for PGI2, PGE1 and PGD2 respectively). Results from biological and infrared stability studies demonstrate that both PGI2 and PGE1 are stable for extended periods of time when dispersed within hydrophobic polymer matrices, an important consideration in the design of nonthrombogenic, prostaglandin controlled release polymers. Finally, both PGE1 and PGI2 controlled release polymers inhibit platelet aggregation in contacting blood, of which PGE1 produced greater platelet aggregation inhibition (90% inhibition) than did PGI2 (75% inhibition). However, PGE1 controlled release polymers significantly reduced platelet adhesion (11.25 +/- 3.68 platelets/mm2) compared to control polymers (50.65 +/- 8.8 platelets/mm2) while PGI2 controlled release polymers demonstrated no improvement in platelet adhesion (25.00 +/- 18.61 platelets/mm2) relative to control polymers (30.43 +/- 7.62 platelets/mm2). One cannot conclude that the lack of reduced platelet adhesion on the PGI2 controlled release surfaces is due to the instability of PGI2. The fact that significant inhibition of platelet aggregation in both blood fractions which contacted the PGI2 controlled release surfaces occurred substantiates that the released PGI2 was active. It must be concluded that PGI2 does not affect platelet adhesion. It is interesting to note that less platelets adhered to the PGI2 control PVC surfaces than on the PGE1 control PVC surfaces. The PGI2 control PVC surfaces were equilibrated with a TRIZMA buffer in 5% dextrose (to provide isotonicity) while the PGE1 control PVC surfaces were equilibrated in isotonic phosphate buffer saline.

Heparin immobilized to polymer surfaces via different length diaminoalkane spacer arms was evaluated for anticoagulant activity and for platelet interactions. The anticoagulant activity of the immobilized heparin, as determined by APTT assays, was found to increase with increasing spacer arm length. Variations in spacer arm length produced no affect on platelet retention or PF 4 release for heparin immobilized materials. To investigate immobilized heparin-adsorbed plasma protein interactions, XPS analysis of heparinized surfaces, before and after plasma contact, was conducted. Immobilized heparin was not able to penetrate adsorbed plasma protein layers with any spacer arm length evaluated, indicating that immobilized heparin does not directly interact with platelets.

Covalently bound conjugates of human serum albumin and heparin were prepared as compounds which could improve the blood-compatibility of polymer surfaces either by preadsorption or by covalent coupling of the conjugates onto blood contacting surfaces. The conjugates (10-16 weight % of heparin) were obtained by a condensation reaction between albumin and heparin using 1-ethyl-3-(dimethylaminopropyl)-carbodiimide. Unreacted albumin and heparin were removed by diethyl-aminoethyl (DEAE)-cellulose and Cibacron Blue Sepharose chromatography respectively. The activity of the heparin component incorporated in the albumin-heparin conjugates (Ac) was compared with that of the heparin used for the synthesis of the conjugates (Anat) by thrombin time, inhibition of Factor Xa and the activated partial thromboplastin time (APTT) assays. The Ac/Anat ratio for the above assays was as follows: Thrombin time 1.25, Factor Xa inhibition 0.5. and APTT 0.5. Gel filtration chromatography showed broad-molecular weight distributions. The conjugates were fractionated using immobilized antithrombin III (ATIII). High ATIII and low ATIII affinity conjugate fractions showed the same behavior as ATIII fractionated heparin with respect to thrombin times and Factor Xa inhibition.

The adsorption of antithrombin III (AT III) onto polystyrene surfaces preadsorbed with albumin or albumin-heparin conjugates was studied using a two step enzyme immuno assay. When AT III-buffer solutions were used, the highest adsorption values were measured on high affinity albumin-heparin conjugate pretreated surfaces. Less AT III adsorption was found on nonfractionated albumin-heparin conjugate preadsorbed surfaces. AT III adsorption could also be detected on low affinity conjugate and albumin coated surfaces. When AT III was adsorbed from plasma or plasma dilutions with buffer, only AT III on surfaces preadsorbed with high affinity or nonfractionated albumin-heparin conjugate was found. These results demonstrate that the heparin moiety of the conjugate is directed to the solution phase whereas the albumin moiety contacts the polystyrene surface.

Owing to the chemical instability of prostacyclin, the direct immobilization of this prostaglandin has not been successful. A new procedure is described for the preparation of immobilized prostacyclin based on the conversion of immobilized prostaglandin F2 alpha to immobilized prostaglandin I2-Materials thus prepared show dramatic antiplatelet effects with regard to platelet aggregation and platelet adhesion. Radioimmunoassays of plasmas used in in vitro platelet tests and of buffers used in prostacyclin leakage studies established that these effects are not due to the release of prostacyclin from the respective immobilization substrates.